Oligonucleotide-Based Electrochemical Biosensor for Hg2+ Using Methylene Blue as a Redox Indicator
Robert Ziółkowski , Marta Maria Jarczewska , Łukasz Górski , Elżbieta Malinowska
AbstractGold electrodesmodified with short-chain ss-DNA oligonucleotides were used for trace-level voltammetric determination ofmercury cation. External redox marker, methylene blue, was employed for these measurements. Due to the competition between Hg2+ and methylene blue, current signal decreases proportionally to the analyte concentration. It was shown that 5-SH-(CH2)6-(T)15−3 oligonucleotide, when employed as a receptor layer, induces the strongest electrochemical signal, among all tested DNA sequences. Electrochemical impedance spectroscopy measurements confirmed a specific interaction between the oligonucleotide receptor layer and Hg2+ ions. Proposed biosensor exhibited significant selectivity toward mercury ion, with strong discrimination of other common metal cations. The remarkably low detection limit of 4.63 nmol · L−1 for Hg2+ ions was calculated for proposed biosensor. The usefulness of developed biosensor was verified by its application for analysis of Hg2+ in aqueous samples.
|Journal series||Journal of the Electrochemical Society, ISSN 0013-4651|
|Publication size in sheets||0.5|
|ASJC Classification||; ; ; ; ;|
|Score|| = 40.0, 01-02-2020, ArticleFromJournal|
= 40.0, 01-02-2020, ArticleFromJournal
|Publication indicators||= 3; = 3; : 2013 = 1.309; : 2013 = 2.859 (2) - 2013=2.903 (5)|
|Citation count*||1 (2015-02-05)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.